This invention relates to a system for, and a method of, removing a component from immersion in a liquid. In particular, the invention relates to the removal of a used liquid treatment component from a container in a convenient manner, whereby any drips of liquid from the component are substantially prevented from contacting the user and any other part of the equipment from which the component is removed. The invention finds particular, though not exclusive, application in a photo-processing system, for example in the removal of a used cathode from an electrolytic silver recovery system, or the removal of a filter cartridge or an ion exchange column. The invention also extends to the replacement of the removed used component with a fresh component.
Although the invention has broader application, for convenience the description will generally relate to its usage in a photo-processing system, and specifically to the removal, and replacement, of a cathode of an electrolytic silver recovery system thereof.
A silver recovery cell, or cartridge, contains a cathode on which silver is plated during operation, for example during the recovery of silver from a fixer solution in a tank of a photo-processor. When the cathode is fully loaded with silver, it has to be removed from the cell by the user. The cathode may be of the reusable type, in which case the silver is removed and the cleaned cathode is replaced in the cell; the silver being sent to a refiner. However, this operation of removing the silver from a cathode is both messy and inconvenient. This inconvenience is reduced when a disposable cathode is used, in which the cathode is generally made of a low-cost conductive material which can be smelted along with the silver. Typical materials for such a disposable cathode are graphite impregnated plastic, graphite foil laminated to plastic sheet, and plastic sheet painted with conductive ink. For a recovery cell having a disposable cathode, the user simply removes the cathode and replaces it with a fresh one; the used cathode then being sent in its entirety for refining.
U.S. Pat. No. 5,370,781 discloses a disposable cathode for use in an electrolytic cell, in which the action of screwing down a lid of the cell both seals the cell and makes electrical contact with the cathode. When the cathode is fall of silver, the lid is unscrewed and the wet cathode is removed either by hand or by means of a tool which grasps holes in the top of a cylindrical wall of the cathode. The cathode is removed from the cell and placed in a bag and sealed for transport to the refiner. The operation of removal, and exchange, of the cathode is still messy and requires some skill on the part of the user to avoid contact between any liquid dripping from the cathode and the user and/or associated equipment.
U.S. Pat. No. 5,203,979 also discloses a disposable cathode, and whilst its large size reduces the frequency of changing, the cell must be drained in order to change the cathode, so that bolts passing through the cathode and the cell wall may be released. Removal of the cylindrical cathode is done either manually or by a tool. This operation is both time consuming and messy, especially bearing in mind that the wet cathode may weigh up to several kilograms.
U.S. Pat. No.4,834,849 discloses yet another type of disposable cathode construction in which the cathode is in the form of conductive paint on a plastic substrate. Replacement of the cathode requires the cell to be drained of its photographic fixer solution, and although the extent of the manual operation is reduced, pouring of liquid, which may cause spills and drips onto associated equipment, is still involved. This method is, therefore, likewise not suited to operation of the cell in an office-like environment.
It is an object of the present invention to provide a system and method that enables a wet component to be removed from immersion in a liquid easily and rapidly, without the need for draining and re-filling of the containment vessel, whilst minimizing not only contact between the user with the liquid, for example a photographic fixer solution, but also with the silver contained therein, and also whilst containing any drips from the wet component in a safe manner during and after removal.
In accordance with one aspect of the present invention, there is provided a system for removing a wet component from a canister for containing a liquid, comprising:
a canister which, in operation, removably contains the component at least partially immersed in the liquid;
a transport housing arranged to receive the component for transport away from the canister;
interengaging means for temporarily locating the transport housing in a position adjacent the canister, and preferably secured thereto; and
a liquid collector arranged to be disposed between the canister and the transport housing so as to collect any liquid released from the component as the component is transferred from the canister to the transport housing.
It will be appreciated that at the time of removal of the component from the canister, the canister may still contain solution, or the solution may have recently been drained therefrom leaving the component still wet.
By xe2x80x98canisterxe2x80x99 is meant a vessel of any shape, capable of containing liquid and into which the component is at least partially immersed at some time during operation.
By xe2x80x98transport housingxe2x80x99 is meant a receptacle, rigid or flexible, of any shape capable of receiving the component.
By xe2x80x98interengaging meansxe2x80x99 is meant any means rigid or flexible, integral with or separate to, the transport housing capable of locating the transport housing adjacent the canister.
The interengaging means may locate the transport housing in a predetermined spatial relationship with the canister, for example alongside or above the canister. The liquid collector may be deployable so as to extend between the canister and the transport housing. In one embodiment, the transport housing is located a fixed distance laterally from the canister so that deployment of the liquid collector will result in its correct positioning between the canister and the transport housing. This is particularly convenient when the liquid collector is relatively rigid.
Advantageously, the liquid collector may be associated with, for example by being retained on or in, the transport housing. The liquid collector may then be unfolded from the transport housing when the latter is secured to the canister. Unfolding of the liquid collector is to be understood as including not only opening it out from an overlapped configuration, but also unfurling, unwinding or otherwise flattening it out from a crumpled state.
Introduction of the wet component into the transport housing may be arranged to carry the liquid collector with it, so that its return to the housing is achieved without any risk of contact between the operator and the liquid.
In a preferred system, the component is fixed to a lid of the canister. Transfer of the component to the transport housing is then achieved by detaching, for example unscrewing, the lid from the canister and attaching, for example screwing, the lid onto the transport housing so as to provide a lid thereof. It will be appreciated that the lid may form a seal onto each of the canister and transport housing, thereby safely to contain the liquid therein.
The interengaging means may comprise a support member extending laterally of the canister for securing the transport housing to the canister. The support member may be generally planar, and may be attached to the canister, or to an enclosure thereof. Preferably the support member has an aperture therein for receiving the transport housing. The aperture may be such as to enclose the total periphery of the transport housing, or may comprise an open ended slot into which the housing may fit. Alternatively, the interengaging means may comprise a clamping member, which may be affixed to the transport housing, arranged to engage with a cooperating member fixed to the canister or to an enclosure thereof.
Advantageously, the liquid collector forms part of, and is carried by, the transport housing, so that any drips collected thereby may be safely removed and conveniently dealt with away from the vicinity of the canister.
In one embodiment the liquid collector is arranged to unfold from the transport housing so as at least partially, and preferably substantially entirely, to surround the canister when the transport housing and the canister are interengaged. To this end, the liquid collector may be apertured so as to pass over the top of and to enclose the canister. The aperture may be in the form of an open ended slot, to extend, for example, for an angle of arc of approximately 270xc2x0 around the canister.
The liquid collector may comprise a material for retaining the liquid, and may be an absorbent or adsorbent material. Examples of absorbent material include cotton wadding, blotting paper, sponge and synthetic absorbent composites. In another configuration, the liquid collector may comprise a tray having a peripheral wall that forms a containment barrier around the canister and the transport housing for any liquid dripping from the transferred component. In this configuration, the drip tray in its folded configuration may form a seal for the liquid when folded back onto the transport housing containing the transferred wet component.
The liquid collector may be formed integrally with the transport housing.
The transport housing may be arranged to be located over the canister, and the action of mounting the housing on the canister may be arranged to deploy the liquid collector. The liquid collector may be operable, for example comprising flaps or a rim, by the action of mounting the transport housing on, or removing it from, the canister.
The transport housing may include a flexible bag, of a material that is impervious to the liquid. An operator may then remove the wet component from the canister and transfer it to the transport housing using the bag as a glove, or sleeve, for protection against the liquid.
The interengaging means may itself form part of the transport housing.
The transport housing may be arranged to be mounted on top of the canister, with the liquid collector located around an opening in the top thereof.
The liquid collector may comprise a bag for receiving the component from the canister, and co-operates with interengaging means for retaining the liquid.
Advantageously, the transport housing when it is brought up to the canister, includes a fresh component therewithin that is to take the place of the said, used, component that is removed from the canister. Thus, when the component is attached to a lid, the fresh component may be secured in the transport housing by means of a screw on lid, which is then transferred to the canister so as to form a sealed lid therewith, whilst the used component is secured in the transport housing by means of its screw-on lid, for safe removal from the equipment with which the canister is associated.
The canister and the transport housing, and preferably also the component, may be of generally cylindrical configuration.
In a preferred embodiment, the system of the present invention forms part of a photoprocessing system. For example the canister may comprise an electrolytic cell for the recovery of metal, for example silver, from a solution, which may be a photoprocessing solution, and the component may comprise a cathode of the cell. Alternatively, the canister may comprise a housing for a filter, or an ion exchange column, and the component may comprise a filter cartridge or element of the column.
In accordance with a further aspect of the present invention, there is provided a method of removing a wet component from a canister for containing liquid, wherein a transport housing for transporting the component away from the canister is temporarily located adjacent, for example on, the canister, and wherein a liquid collector is disposed between the canister and the transport housing so as to collect any liquid released from the component as the component is transferred from the canister to the transport housing.
It will be appreciated that the method may be used with the system described above for the removal, and preferably exchange, of a component immersed in liquid.
In accordance with a still further aspect of the present invention, there is provided a transport housing for a component carrying liquid, wherein the housing comprises:
a chamber for receiving the component therein;
means for temporarily locating the housing adjacent a canister in which the component is, in operation, disposed at least partially immersed in a liquid; and
a collector carried with, for example attached to, the housing for collecting any liquid released from the component during transfer to the housing. The liquid collector may be arranged to be deployed from the transport housing when the transport housing is located adjacent the canister so as to extend therebetween so as thereby to collect the liquid.
By xe2x80x98chamberxe2x80x99 is meant an enclosed space capable of receiving the component therein.
Advantageously, the transport housing will be arranged to be located side-by-side with the canister so that the deployed liquid collector forms a substantially planar surface therebetween. Alternatively, the housing may be located on top of the canister.
The invention is particularly applicable where the component is to be removed through the top of the canister, thus avoiding the need for any draining or refilling thereof.
The canister may be in the form of the silver recovery electrolytic cell described in our contemporaneously-filed patent application number GB 985169.9.
Although the liquid collector may be provided as a relatively rigid component, at least to the extent that it is self supporting, it is also envisaged that it could be formed as a more flexible element. In this latter aspect, it is envisaged that the liquid collector may be stored inside the transport housing, alongside or beneath a fresh component if included therein. Upon mounting adjacent the canister, the collector may be unfolded, and flattened out if necessary, and positioned between the transport housing and the canister. To assist in this, the liquid collector may be slit from its outer periphery inwards to an aperture that forms a push fit over the canister. Advantageously, the liquid collector may have an aperture to be positioned over the transport housing, the size of the aperture being less than that of the component. In this configuration, insertion of the component into the transport housing after its removal from the canister will serve to fold back the liquid collector into the transport housing.
The securement of the transport housing to the canister, and the provision of means therebetween for collecting any liquid that drips from the component as it is transferred from the canister to the transport housing, ensures that none of the liquid will fall onto an operator or onto equipment with which the canister is associated. This is particularly advantageous when the liquid involved is toxic, flammable, or corrosive, or otherwise hazardous, being, for example, a solvent or an acid.
Particularly when the component is attached to a lid of the canister, any risk of contact by the user with the liquid, or with any other material adhering to the component, is minimized.
Arranging for the liquid collector to be folded away, and particularly to be folded onto or into the transport housing, results in a very simple system. Although when the liquid collector is provided as a relatively rigid element, a certain degree of registration needs to be achieved between the transport housing and the canister, this can be obviated by making the collector of a more flexible material.
Since the liquid collector will be able to retain only a certain amount of liquid, it being primarily arranged to trap drips from the transferred component, care and time should be taken when removing the component from the canister so that as much liquid as possible is allowed to drain back into the canister, before the component is transferred to the transport housing.
Where the component is an electrical component, as for example being a cathode of an electrolytic cell, then electrical connection to the component can advantageously be made via a lid of the canister, such that the component, preferably together with the lid, can be removed without the need to drain the cell of its liquid. In this respect, the system disclosed in our contemporaneously-filed patent application number GB 9815172.3 finds particular application.